The point of breeding (imo) is to breed the best dogs you possibly can, with a goal in mind.

What is your goal in breeding these dogs?

Better health? No. You would be health testing for the appropriate things.Show dogs? No. This isn't even too important, not all dogs need to be show quality.Dogs that are somehow different or better than the thousands of other Chihuahuas being bred? Nope. There are a ton of Chihuahuas in shelters/rescues/pounds that are just like your dogs: not to standard, no titles, no health testing, nothing special.

What makes your breeding dogs more special than the dogs you rescue? Because properly bred dogs should have something special about them, that sets them apart from the same breed dogs in rescue. Doesn't matter if it's looks (to standard), awesome dogs in their pedigree, titles, ect. But to breed dogs that are no different than the other "non standard, no title, no health testing, no NOTHING" dogs in rescue is downright stupid. You are ruining the breed that you claim to love.

Why not do it right?

Would you consider at least getting your dogs health tested? And getting better breeding stock that is to standard?